Can you eat a crystal?

"How do you imagine a crystal?" This was the question posed to children entering The Room of Crystals organized by crystallographers at the Chemistry Department of the University of Parma on September 27th, 2013.

"Crystals are diamonds and gems, they are shiny and they sparkle!" was always the answer given by 6- to 13-year-old schoolchildren.

"Then, can you eat a crystal?" "Noooo!!!!" "Well, I’ll show you: I will eat a crystal! Look!" and after eating a grain of table salt, we began to tell them about crystals of sugar, crystals of salt, crystals in chocolate, crystals in toothpaste and even in chewing-gum, inviting them to look at the different samples through a microscope. And then the story extended to crystals growing in the center of the Earth - beautiful fluorescent minerals were shown to them- and then we told them that crystals can be inside computers and that they also grow on spaceships, and silicon wafers and CdTe samples grown in microgravity were displayed.

After explaining that crystals are everywhere, their ordered nature was illustrated using drawings on the blackboard, and children were invited to build their own models of the Bravais lattices by using marshmallows and skewers. The surprise and joy shining in their eyes was a welcome and deserved reward for the trouble it took, later on, in cleaning tables and microscopes from sticky candies, toothpaste and chocolate fingerprints.

The show was completed by a beautiful display of splendid mineral samples provided by the Gruppo Mineralogico Paleontologico Naturalistico Parmense, and by a tour through a preview of panels from the exhibition 'CRISTALLI!'. This exposition, initiated by crystallographers in Padua, began on October the 6th and will be travelling across Italy to reach Parma in May 2014.

After all this learning, some reward was due, and so children were invited to take part in the quiz 'Who is Dorothy?' to win an 'artificial geode' consisting of copper sulphate and potassium phosphate crystals grown inside nutshells. Cardboards telling facts about the life and discoveries of Dorothy Hodgkin were hidden around the building; children had to find the clues, and then report their answers in order to get the coveted prize: their own crystals in a nutshell.

Over 400 visitors to the ‘Room of Crystals’ learnt about the beauty and importance of crystallography. The events planned in Parma for the International Year of Crystallography were warmly advertised, and we look forward to having an enthusiastic public for the initiatives of next year.

The 'Room of Crystals' was one of the events taking place during the "Researchers’ Night", a day fully devoted to promote science, organized by the Department of Chemistry, the Department of Physics and Earth Sciences, the CNR-IMEM, the Department of Food Sciences of the University of Parma on September 27th, 2013.